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System.out.println(" " + 7 + 2 );
System.out.println( 7 + 2);
why the output first line is 72 and it's 9 for next line
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" " + 7 + 2 = 72, because the first element is a
string, therefore it will treat the 7 and 2 being added to a string i.e. 72 being added to the blank string.
7+2 = 9, because the first element is an int and therefore it will add 2 as an int rather than a string.